Amethyst
Quartz var. Amethyst · Semi-Precious Gemstone
Crystal System
Trigonal, with a massive or tumbling habit (originally part of a geode or prismatic crystal aggregate)
Mineral Group
Silicates, specifically Tectosilicates
Chemical Formula
SiO2
Formation Process
Hydrothermal and low-temperature magmatic processes where silica-rich fluids deposit quartz within cavities, colored by natural irradiation of trace iron impurities
About This Crystal
A tumbled, polished gemstone of translucent to semi-transparent purple quartz, featuring characteristic pale and darker violet color zoning with faint white quartz bands running across the midsection
Physical Characteristics
Purple body color with white bands, white streak, conchoidal fracture, absence of true cleavage, specific gravity of approximately 2.65, and a brittle tenacity
Optical Properties
Uniaxial positive optical sign, doubly refractive, with weak pleochroism showing reddish-purple to bluish-purple shades from different angles
Hardness & Durability
Origin Region
Brazil, Uruguay, Madagascar, Zambia, and the United States; forms typically in volcanic gas cavities, hydrothermal veins, and pegmatites
Hardness & Durability
Mohs hardness of 7, good durability and wearability for everyday jewelry, resistant to scratching by most common materials except harder minerals
Care & Maintenance
Easy to maintain; clean with warm soapy water, avoid prolonged direct sunlight to prevent fading, and store separately to avoid scratching softer gemstones
Rarity & Value
Common; widely available globally with values varying based on color saturation, transparency, and size, ranging from inexpensive tumbled stones to higher-tier faceted gems
Special Characteristics
Displays natural color zoning and banding; exhibits piezoelectric and pyroelectric properties under mechanical or thermal stress
Lore & History
Historically worn by ancient Greeks and Romans to prevent intoxication; widely associated in modern crystal healing with the third eye and crown chakras, promoting tranquility, balance, and spiritual awareness